[Fluidguy]

Hello guys,

I am having a problem with CFD. I am trying to figure out what boundary conditions I have to use if I want to get a propper image of air flowing through a tube. In the tube I added a aperture to raise the preassure at the front and get a higher speed at the exit of my aperture. The boundary conditions I am using at the moment are:

INPUT:
speed: 10m/s
pressure at the entrance: 0,2Bar = 20mBar excess hydrostatic pressure

OUTPUT:
I dont want to define any conditions for the area behind the aperture. Let's say I don't know anything about this area and I want my PC to solve this task/fiction of mine. I want him to show me what speed/pressure I would get at/behind my aperture, with this szenario of mine.

The thing is, if I am not able to create these easy tasks and get propper answers, I will never be able to understand even more complexe structures. So that's why I want to understand the basics.

I hope someone can help me with my problem.



Thanks a lot in advance,
Fluidguy

[matt.brown.ae]

Can you clarify what you mean by 'proper image of air flowing through a tube'? Are we talking about velocity distribution, streamlines, pathlines, pressure distribution, etc?

Can you post a screenshot or two of your geometry? I am not following your description.

Thanks,
Matt